Demographic Transitions Population Pyramids

Population Pyramids – Shows the percentage of the total population, usually in 5 year age groups, with youngest on bottom, oldest on top. Every country or regions stage of demographic transition gives it a distinctive population structure. Shape is determined primarily by crude birth rate in the community.

US Population Pyramid

Demographic Transition and Age Age Distribution -Extremely important in understanding similarities and differences among countries. Dependency Ratio – The most important factor when talking about age distribution. Three Age Groups 0-14 15-64 65+ Stages and age – As people pass through the stages of demographic transition, the percentage of elderly people increases. The higher the stage, the higher the number of dependants, and the more money required to take care of the population.

Demographic Transition and Sex Ratio Sex Ratio – The number of males per hundred females. Varies and in general more males than females are born, but males have higher death rates. As age goes up, so does the ratio of females.

Countries in different stages Stage 1 – None Stage 2 – Cape Verde Antimalarial campaign Environmental issues Broad base

Stages 3 & 4 Stage 3 – Chile Stage 4 – Denmark Outside of Europe and North America Vigorous Government funded family planning Stay due to reversal of policy Stage 4 – Denmark Roughly equal CBR and CDR Zero population growth Percentages of youth and elderly are the same